Effect of Cu on optical properties of TiO2 nanoparticles

Abstract

Cu-doped TiO2 nanoparticles were prepared; the effect of Cu on optical properties of TiO2 nanoparticles to shift its absorption edge toward visible light region was studied. By using a green synthesis mechanism were obtained TiO2 nanoparticles, and trough wet -impregnation method using copper sulfate as precursor were obtained Cu-TiO2 nanoparticles. The synthesized material was characterized by Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), Energy Dispersive Spectroscopy (EDS), UV-VIS diffuse reflectance spectroscopy (UV-Vis/RDS). FTIR characterization have been made to confirm the formation of TiO2. Through EDS analysis was determined the ion dopant percent in each sample. Morphological properties and particle size were identified by SEM micrographs, which disclose a spherical shape with an average size between 70 and 27.3 nm. UV-VIS/RDS spectrum showed that the band gap energy decreases with the increase of Cu concentration in TiO2, for that reason, doped nanoparticles had activity under visible light irradiation.

Dye degradation performance, bactericidal behavior and molecular docking analysis of Cu-doped TiO2 nanoparticles

“…Optical electronic excitations to conduction band from valence band are commonly depicted by enhancement of absorbance band with a certain wavelength in obtained absorption spectrum. 59 In acquired spectra, pristine TiO 2 exhibits absorption band around 310 nm, and Cu-doped samples also show this UV absorption band along with absorption tail trailing towards visible region (redshi). 48,55,59,62,63 The slight shi in absorption band up to 400 nm is caused by charge transfer from O 2p to Cu d-states.…”

“…It can be seen in the acquired spectrum that a sizeable absorption band is present between 400-1000 cm À1 that is ascribed to the vibration modes of Ti-O-Ti linkage in TiO 2 nanoparticles which signies the formation of TiO 2 . 59,60 The small absorption band around 1062 cm À1 in doped sample arises due to bonding of Ti-O-N. 60 Observed band between 3300-3600 cm À1 relates to stretching vibrations of hydroxyl group (O-H) and distinct band around 1632 cm À1 is attributed to the bending vibrations of hydroxyl ions (-OH). This vibration band is associated with the protons of physisorbed water in prepared samples.…”

“…This vibration band is associated with the protons of physisorbed water in prepared samples. 59,61 According to the literature, titanium oxide preserves adsorbed undissociated water molecules owing to strong Lewis acidity of coordinatively unsaturated Ti 4+ surface sites. 59 UV-vis spectroscopy was used to study optical properties of prepared samples in terms of maximum absorption of ultra-visible light, band shi, and determination of band gap energy, as shown in the spectra displayed (200-700 nm) in Fig.…”

Impedance analysis of TiO2 nanoparticles prepared by green chemical mechanism

“…TiO2 nanoparticles were synthetized by green synthesis method [11], [12], using extract derived from leaves of lemon grass, the process was divided in two stages: natural extract elaboration and synthesis of TiO2 nanoparticles. Titanium tetraisopropoxide (TTIP 95% pure) manufactured by AlfaAesar was used as a TiO2 precursor, ethanol (CH3CH2OH) manufactured by Panreac was used for washing nanoparticles.…”

“…The extract was filtered several times and concentrated by evaporation, heating it at 60°C. For synthesis of pure TiO2 nanoparticles, an aqueous solution of 5mM of titanium isopropoxide was stirred by ultrasound during 30 min, 15 ml of the aqueous extract of lemon grass was added in 85 ml of isopropoxide solution with continuous stirring at 175 rpm and room temperature for 24 h. Synthesized nanoparticles were removed by centrifugation and dispersed in ethanol and then in distilled water to wash out impurities, after that, they were calcined in a muffle furnace for 3 h, starting at 300°C until 550°C [11].…”